A video of the Canadian astronaut singing David Bowie's "Space Oddity" from the International Space Station has been zipping around the Web at light speed since it was posted Sunday. The five-minute clip features Hadfield singing a modified version of the tune and strumming an acoustic guitar while floating through a space module, more than 200 miles above the Earth.

By Monday morning, it had more than 1 million views on YouTube, 3,000 comments on Reddit and was being widely shared across social networks.

Astronauts on the International Space Station get to do the coolest experiments. And sometimes the simplest ones can be the most impressive.

Canadian astronaut Chris Hadfield demonstrates what happens when you wring out a soaking wet washcloth in zero gravity. The idea came from two high school students in Nova Scotia who won a contest to design a simple science experiment to be conducted on the ISS. The experiment had to use materials that were already available on the space station and was selected out of almost 100 entries.

Watch the video above to see the incredible effect of weightlessness on the water absorbed by the washcloth.

What are some simple experiments you would like to see conducted in space? Let us know in the comments below!

Crying probably isn’t on the top of the list of official experiments being explored on the International Space Station, but that doesn’t stop astronaut Chris Hadfield from demonstrating the phenomenon of human tears in space.

The Canadian ISS commander recently took time to answer a question he says he commonly receives: What happens to your tears when you cry in space? Hadfield's video demonstration will make the inner nerd in you shout with glee.

Hadfield uses a bottle of drinking water to place droplets in his eyes and then proceeds to blink and move around. He shows off this bizarre reality: Tears don't fall in space.

Check out the video to see what happens. Trust me, you’ll understand why Hadfield says that if you’re going to cry in space, bring a hankie.

British singer Peter Gabriel got a brief serenade from a member of the International Space Station crew on Wednesday during a visit to Mission Control in Houston.

Canadian Chris Hadfield, Expedition 34's flight engineer, strummed a few chords of Gabriel's hit "In Your Eyes" during a nearly 12-minute chat with Gabriel and his family.

Hadfield told Gabriel that he recorded two songs in space. The first, co-written with his brother, is a "space Christmas carol" called "Jewel in the Night." The second, a space-to-Earth collaboration with Canadian band Barenaked Ladies, is called "I.S.S. (Is Somebody Singing)."

After his great feat of becoming the first man on the moon, Neil Armstrong’s career seemed destined for stardom: He played the leading role, along with his peers, Edwin Aldrin and Michael Collins, in many triumphant parades and awards ceremonies.

But he shied away from the spotlight. After being selected as deputy associate administrator for aeronautics at NASA, he resigned in 1971 to become an aerospace engineer professor at Cincinnati University, where he served until 1981.

After that, Armstrong served as president of aerospace technology companies, Computing Technologies for Aviation and AIL Systems, as well as honorary positions at institutions such as the Society of Experimental Test Pilots and the International Astronautical Federation. FULL POST

Editor's note: We're listening to you. Every day, we spot thought-provoking comments from readers. Here's a look at what readers are saying.

Earth's largest satellite helps create our tides and makes moonlit rides possible. The white ball adorned in shadows and craters has long confounded and beckoned us, and Apollo 11 Commander Neil Armstrong became the first human to set foot on the moon's dusty surface. Buzz Aldrin and Michael Collins were with him on a mission that inspired many more small steps.

News that Armstrong had died got our readers reminiscing about the many little impacts from mankind's giant leap into the future.

"I was born in the 1970s and back then you just didn't throw out a name for your child. There was an importance to naming a child. My parents thought someone to walk on the moon was significant. They wanted to capture the hope."

He says he felt great sadness when he learned that Armstrong had died.

"I was talking to my dad, and he said your godfather passed away. My first reaction was, 'I haven't seen my father's side in ages,' and then my father said Neil Armstrong died," he wrote, and noted all the ways Armstrong had inspired him.

"Neil Armstrong, thank you for your accomplishments, your inspiration, for allowing us to do great things (reaching Mars for example), and most importantly, for giving us a name to remember. You can be sure that I will continue to speak about you for generations to come, and people will always know, why my name is Neil!"

CNN) - China made history Saturday when it launched a spacecraft sending the nation's first female astronaut in space.

The Shenzhou-9 launched Saturday afternoon, carrying Liu Yang and two male astronauts, Jing Haipeng and Liu Wang. State media aired the launch held at a satellite center in Jiuquan.

Liu, 33, was the deputy head of a flight unit in the nation's air force, according to China's Xinhua news agency.

She is a veteran pilot with 1,680 hours of flying experience, and excelled in space testing after two years of training.

If all goes well, the Shenzhou-9 will dock with China's orbiting space laboratory, making the nation the third after the United States and Russia to complete a manned space docking.

The Shenzhou-9 spacecraft and its carrier rocket as seen Saturday in northwest China's Gansu province.

Participation of women in space will aid training, improve flight crew equipment and expand knowledge on the physical and psychological effects of space on women, said Wu Ping, a spokeswoman for China's manned space program.

There are three more men in space Tuesday than there were 24 hours ago. Monday night at 11:01 p.m. EDT, the remaining three members of the Expedition 31 crew launched aboard the Soyuz spacecraft and are now on their way to the International Space Station.

Monday night's launch, from Baikonur Cosmodrome in Kazakhstan, was preceded by the usual pre-launch activities: the crew signed the door of their crew quarters, were blessed by a Russian Orthodox priest, and said goodbye to their families before getting their suits checked and boarding the spacecraft.

Onboard with the three men, acting as this flight's talisman, was a stuffed Smokey Bear. Traditionally, Soyuz crews fly with a small toy hanging from the top of the crew compartment that acts as a gravity indicator: when the toy floats, the crew's in orbit. (Once it was an Angry Bird!)

If you missed it (or if you didn't and just want to see it again), NASA's posted the video of the launch.

The Soyuz will reach the International Space Station and dock on Wednesday at 12:38 am EDT.

There we were on Saturday night, just the two of us. John Glenn, who 50 years ago today became the first American to sit alone atop a 125-ton rocket and shoot around the world three times at more than 17,000 miles an hour.

Glenn's mission made him a national hero who eventually left NASA and later served four terms as a U.S. senator from Ohio.

But he couldn't stay away. Fourteen years ago, at age 77, he returned to orbit - on a much heralded shuttle mission aboard Discovery that put him in the history books again as the oldest person to travel to space.

Now, at 90, Glenn is still lean and fit.

Would he go again? “I’d go tomorrow if I could,” he said.

Of course, the shuttle program is over, which Glenn told me he’s not happy about.

I asked Glenn what was going through his head while he sat in that Mercury capsule waiting to lift off. It seemed like the whole world was talking about the race with Moscow to dominate space and rising Cold War tensions.

No, he said. He didn't feel any pressure from the space race or the Cold War. The Soviet Union had already orbited a man around the world, Glenn told me.

He was absorbed in the task at hand.

“You just wanted to do the best job you could do,” he said.

There was no time then to think about the bigger picture.

Everything was a “change of status,” Glenn said. “Check the pressures. Change of status. It lights and you’re going, 'Change of status. Do I have orbital speed? Change of status.' ”

'Godspeed, John Glenn': 'I didn't hear it'

Gaining orbital speed was a big deal. Scott Carpenter knew it.

Carpenter - who was Glenn’s back-up for the flight - sat in Mission Control on that day 50 years ago. Three months later, Carpenter would become the second American to orbit the Earth.

In fact, it was Carpenter who uttered those famous words as Glenn lifted off: “Godspeed, John Glenn.”

I asked Carpenter, who was now sitting just a few feet away from where Glenn and I had been chatting, if he'd thought about those words beforehand.

“I never thought about it,” Carpenter told me. “What John needed that no American had before was speed." The previous Mercury flights - piloted by Alan Shepard and Gus Grissom - had been suborbital. They didn’t need the velocity Glenn needed to make it to orbit.

What I didn’t know was that Glenn was on a different communications channel when Carpenter said those historic words.

But 36 years later aboard Discovery, Carpenter was back in Mission Control and said it again, “Godspeed, John Glenn.” That time Glenn says he heard it in real time.

Astronaut/aquanaut

Carpenter, a Navy man, has a love for outer space and inner space.

When he left NASA, he explored underwater adventures as an aquanaut in the Navy’s Man in the Sea Project - at one point living and working on the ocean floor for 30 days straight. Later Carpenter served as director of the Navy’s Aquanaut Operations.

“I still can’t make up my mind whether I like outer or inner space better,” he said - adding with a smile, “But there’s a difference in glory.”

Editor's note: CNN contributor Bob Greene is a best-selling author whose books include "Late Edition: A Love Story" and "Once Upon a Town: The Miracle of the North Platte Canteen."

For half a century, the world has applauded John Glenn as a heart-stirring American hero. He lifted the nation's spirits when, as one of the original Mercury 7 astronauts, he was blasted alone into orbit around the Earth; the enduring affection for him is so powerful that even now people find themselves misting up at the sight of his face or the sound of his voice.

But for all these years, Glenn has had a hero of his own, someone who he has seen display endless courage of a different kind.

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